呼伦湖浮游植物调查与营养状况评价

系统地对呼伦湖浮游植物现状进行了调查和监测,调查结果显示,呼伦湖共有浮游植物142种属,隶属8门、22目、40科,其中绿藻门69种,硅藻门29种,蓝藻门27种,裸藻门5种,甲藻门3种,隐藻门2种,黄藻门4种,金藻门3种。以绿藻、蓝藻和硅藻为优势种属。浮游植物平均生物量为6.995mg.L-1。在此基础上,分别以浮游植物种类生态学指标和PCQ模型对呼伦湖水质进行评价,并验证了PCQ模型用于富营化评价的可行性,结果表明呼伦湖处于富营养状态。     

巢湖藻类组成与环境因子典范对应分析

2008年5月—2009年5月对巢湖藻类组成及水质的季节变化进行了逐月调查研究。鉴定的藻类共6门31属48种,其中绿藻比例最高,占47.9%。藻类优势种群为蓝藻门的铜绿微囊藻（Microcystic aeruginosa）,出现频度为90.9%。3个采样点藻类群落组成没有明显差异,藻类物种丰富度指数（Margalef值）和藻细胞密度的变化范围分别为0.10~1.84和（12.65~825.00）×106 cell.L-1,且冬季值较低。同时,叶绿素（1.30~41.10μg.L-1）和总磷（0.06~0.48 mg.L-1）含量分别在秋季和夏季显著高于其他季节。典范对应分析（CCA）显示,藻类种群分布受水环境因子的影响较为明显。整体上,TP是影响巢湖藻类种群分布的重要因素。     

封闭式工厂化养鱼池的浮游植物特性研究

2012年,对封闭式工厂化养鱼池浮游植物的种类、生物量和变化趋势进行了研究。共计检出浮游植物10种。其中蓝藻门2属、3种,硅藻门1属、1种,绿藻门3属、6种。优势种主要有普通小球藻、椭圆小球藻、针形纤维藻。浮游植物的密度和生物量受日常养殖管理影响较明显,生物量为120.6 mg/L~125.4 mg/L,平均值为123.0 mg/L,浮游植物呈现较稳定趋势,说明该系统运行较正常。     

三峡库区3条支流夏季浮游生物现状及多样性分析

为分析三峡库区长江支流浮游生物的群落结构特征及多样性,2015年6月对彭溪河、梅溪河、抱龙河3条支流共选取8个断面进行了浮游生物调查。采集到浮游植物8门74属157种,其中硅藻门种类最多,为18属53种,占浮游植物种类总数的33.76%;浮游植物物种组成呈硅藻-绿藻型,自三峡水库三期蓄水以来未发生显著变化。采集到浮游动物4门52属107种,其中轮虫最多,为23属53种,占浮游动物种类总数的49.53%。通过对8个断面Shannon Wiener指数、Marglef指数和Pielou指数分析可以得出,三峡库区支流水质处于轻度-中度污染。     

洞庭湖典型断面藻类组成及其与环境因子典范对应分析

2010年对洞庭湖6个典型断面进行了浮游藻类生物调查,共鉴定出7门72属（种）,浮游藻类的密度范围在67.2×104～161.9×104cell·L-1;各典型断面间浮游藻类组成以硅藻和隐藻占优势,藻类群落结构存在着明显的差异。藻类Margalef指数及Shannon-Wienner指数范围分别为3.64～4.03和3.03～3.24,水体水质状况良好。应用CANOCO4.5软件对获得的浮游植物数据和环境因子数据进行典范相关分析（CCA）,作出物种与环境因子关系的二维排序图。结果显示,典型断面藻类群落分布受水环境因子影响较为明显,整体上,DO和TN是影响洞庭湖典型断面藻类物种分布格局的主要因素。     

水利开发对二滩水库浮游植物及水质状况季节性影响

2010—2014年连续5 a（春季、夏季、秋季、冬季）对四川二滩水库进行浮游植物及水质定点采样调查,研究水利开发对浮游植物种类组成、数量特征、群落多样性及水质状况的影响。结果表明:（1）水利开发区共检出浮游植物7门251种,绿藻门（Chlorophyta）90种,所占比例为35.86%,对照区共检出浮游植物7门166种,绿藻门68种,所占比例为40.96%,水利开发区和对照区浮游植物种类在夏季和秋季较高,春季和冬季较低;（2）二滩水库水利开发区和对照区浮游植物Shannon-Wiener多样性指数（H）、Pielou均匀度指数（J_P）、Margalef种类丰富度指数（S）在夏季和秋季较高,春季和冬季较低,随季节呈先增加后降低趋势,而浮游植物密度（D）在秋季最低,不同季节浮游植物密度和丰富度指数均表现为水利开发区显著或者极显著高于对照区,多样性指数和均匀度指数均表现为对照区极显著高于水利开发区（p < 0.01）;（3）水利开发区和对照区水温、pH,TN,NH₄⁺-N,TP,高锰酸钾指数,BOD₅和COD_cr浓度呈一致的变化规律,随季节的变化呈先增加后降低趋势,秋季最高,春季和冬季较低,其中水温在夏季最高,透明度随季节变化呈“V”字形规律,在春季最高,秋季最低,而水温和TP浓度在水利开发区和对照区并没有明显差异;不同季节pH,TN,NH₄⁺-N,高锰酸钾指数,BOD₅和COD_cr浓度均表现为水利开发区高于对照区,局部有所波动,在冬季二者的差异不明显,说明了水利开发对二滩水库冬季水质的影响较小;（4）相关性分析表明二滩水库浮游植物群落多样性与水温和TN浓度呈显著或极显著正相关,与pH呈显著负相关,说明pH、水温和TN含量是影响二滩水库浮游植物多样性的主要因素。     

昭通市淡水藻类绿球藻目调查研究

对云南省昭通市鲁甸县人工湖、砚池山水库、桃源水库等不同水体中的藻类植物进行采集、观察及分类学鉴定,鉴定确定了绿藻门绿藻纲绿球藻目7科23属61种(含变种)。通过对鲁甸县各水体中的绿球藻进行调查研究,补充了昭通市藻类植物种类,为地方藻类研究和水质分析提供数据参考。     

莆田市东圳水库水生态环境现状分析及修复探究

本文主要从东圳水库水生态环境现状着手,通过对2016～2020年东圳水库水质监测结果、2018年3月至2020年11月水库浮游植物的调查结果及藻密度监测数据等开展分析,得出:①东圳水库水质全年处于中营养到富营养状态,水体环境秋季好于春季和夏季,随着东圳水库水环境综合治理项目的推进,水体水质总体趋于变好;②水体中藻类本底...     

武汉月湖沉积物中硅藻的垂直分布与水质变化

采用活塞取样器采集了月湖湖中央2处钻孔沉积物,分析了其中硅藻种类与密度的垂直变化,同时采用^210Pb/^137Cs推测沉积物的沉积速率,关进行了总有机质．生物硅含量分析,以了解月湖各个不同年代的水质变化。结果表明,2个柱状沉积物中硅藻的优势属为：小环藻属、直链藻属、舟形藻属、Cyclostephanos属。Z－1钻孔优势种为：梅尼小环藻、颗粒直链藻、Navicuta porifera、Cyclostephanos tholifomis. Z-2钻孔中优势种为：梅尼小环藻、颗粒直链藻、舟形藻、Cyclostephanos invisitatus。就硅藻密度而言,总趋势是上层最多,平均7．14×10^5～58．65×10^5ind·g^-1,中层其次,平均0．08×10^5-13．98×10^5ind·g^-1,下层最少,平均0．24×10^5-0．64×10^5ind·g^-1.硅藻种类数变化虽然没有明显规律,但种类最少的样品出现在中层,^210Pb/^137Cs测年数据表明中层为19世纪90年代－20世纪70年代。相天分析表明：Z－1孔生物硅与沉积硅藻密度显著正相关（r=0．933,P=0．021〈0．05）,总有机质含量与种类数显著负相关（r=－0．972,P=0．005〈0．05）;Z－2孔生物硅与沉积硅藻密度显著正相关（r=0．985,P=0．002〈0．05）,沉积硅藻密度与种类数显著负相关（r＝－0．933,P=-0．021〈0．05）。研究结果表明,月湖沉积物中硅藻种类与密度的垂直变化可以反映月湖的富营养演化历程：19世纪60年代－19世纪80年代,月湖水质较好;19世纪90年代－20世纪10年代,月湖开始由贫营养状态向中营养状态转变,为水体富营养化开始发生时间;20世纪20年代－20世纪40年代,月湖水体营养等级持续增加,已富营养化;20世纪50年代－20世纪70年代,周边人口数量急刷上升与污水的直接排放导致月湖水质持续恶化;20世纪80年代至月湖截污前这段时期使月湖最终沦为劣五类水体的湖泊。     

大连松树水库浮游植物特征及对环境因子的响应

2017年5—10月,每月2次对松树水库开展浮游植物采样调查,同步监测总氮含量、总磷含量、叶绿素a含量、降水量和库容等指标,考察松树水库浮游植物群落结构组成及密度变化,并进行冗余分析研究浮游植物与环境因子的关系。结果表明:松树水库浮游植物组成为硅藻门-蓝藻门型,随季节性变化明显,其中硅藻门与蓝藻门存在竞争关系;藻类总数、硅藻门密度和蓝藻门密度对水质和水文因子的响应存在不同程度的差异。建议在夏季主要控制有机质,而春秋季着重减少水中氮磷含量,以防控水华的发生。     

Soil algae from a maryland serpentine formation

Algae from serpentine soil samples collected at Soldiers Delight, Maryland (located in the west central portion of Baltimore County) were cultured using an enrichment technique. The algal flora was found to consist of members of the Cyanophyta, Chlorophyta and Chrysophyta (Bacillariophyceae). Composition of the soil flora at the division level is similar to that of more favorable soil types, indicating possible adaptations to high chromium and nickel concentrations and a low Ca: Mg ratio. Among the Cyanophyceae examined were three genera known to contain species which fix N₂. The presence of Cyanophyte genera capable of N₂ fixation suggests possible N input to this generally nitrogen-poor system. Lack of nitrogenase activity in collections of blue-green algal mats during early spring may be due to seasonal variation or Mo deficiency common in serpentine soils.     

Cyanobacterial–algal cenoses in ordinary chernozems under the impact of different phytoameliorants

General ecological and taxonomic characteristics of cyanobacterial–algal cenoses in ordinary chernozems under different ameliorative plants (phytoameliorants) were studied in the Trans-Ural region of the Republic of Bashkortostan. A comparative analysis of the taxa of studied cenoses in the soils under leguminous herbs and grasses was performed. The phytoameliorative effect of different herbs and their relationships with cyanobacterial–algal cenoses were examined. Overall, 134 cyanoprokaryotic and algal species belonging to 70 genera, 36 families, 15 orders, and 9 classes were identified. Cyanobacterial–algal cenoses included the divisions of Chlorophyta, Cyanoprokaryota, Xanthophyta, Bacillariophyta, and Euglenophyta. Representatives of Ch-, X-, CF-, and P-forms were the leading ecobiomorphs in the studied cenoses.     

Ecological-floristic analysis of soil algae and cyanobacteria on the Tra-Tau and Yurak-Tau Mounts, Bashkiria

The species composition of the soil algae and cyanobacteria in the Tra-Tau and Yurak-Tau mountains is represented by 136 species belonging to five phyla: Cyanobacteria (56 species), Chlorophyta (52 species), Xanthophyta (13 species), Bacillariophyta (12 species), and Eustigmatophyta (3 species). Hantzschia amphioxys var. amphioxys, Hantzschia amphioxys var. constricta, Klebsormidium flaccidum, Leptolyngbya foveolarum, Luticola mutica, Navicula minima var. minima, Nostoc punctiforme, Phormidium jadinianum, Phormidium autumnale, and Pinnularia borealis were identified more often than other species. The composition of the algal flora depended on the soil properties; the higher plants also had a significant influence on the species composition of the soil algae.     

Seasonal Variation of Mercury Associated with Different Phytoplankton Size Fractions in Lahontan Reservoir, Nevada

Sampling is conducted during 2006 in Lahontan Reservoir, Nevada to investigate seasonal variation of total mercury (THg) and methylmercury (MeHg) partitioning in different phytoplankton size fractions as a function of point source (fluvial) mercury (Hg) loads, reservoir residence time, and algal growth. Carson River Hg inputs into the reservoir are extremely dynamic with spring loads two orders of magnitude larger than summer loads. Chlorophyll a measurements show two periods of algal growth. A small amount of algal growth occurs March to May. A second more substantial bloom occurs in the late summer, which is dominated by large, filamentous algae. THg concentrations (C _b) and partitioning coefficients (K _d) in total suspended particulate matter (SPM) are highest when fluvial inputs of Hg-contaminated sediment are large and are not necessarily associated with living biomass. However, MeHg K _d in the small size fraction is indirectly related to fluvial loads and more strongly associated with living biomass in the later portion of the summer when algal growth occurs and reservoir residence times are longer. Data suggest size distinction is important to MeHg partitioning in the reservoir. Lumping all sizes into a single SPM sample will bias the analysis toward low MeHg C _b and low MeHg K _d in late summer when Aphanizomenon flos-aquae dominates the phytoplankton assemblage.     

Photosynthetic pigments in soils from northern Victoria Land (continental Antarctica) as proxies for soil algal community structure and function

Although soil algae are among the main primary producers in most terrestrial ecosystems of continental Antarctica, there are very few quantitative studies on their relative proportion in the main algal groups and on how their distribution is affected by biotic and abiotic factors. Such knowledge is essential for understanding the functioning of Antarctic terrestrial ecosystems. We therefore analyzed biological soil crusts from northern Victoria Land to determine their pH, electrical conductivity (EC), water content (W), total and organic C (TC and TOC) and total N (TN) contents, and the presence and abundance of photosynthetic pigments. In particular, the latter were tested as proxies for biomass and coarse-resolution community structure. Soil samples were collected from five sites with known soil algal communities and the distribution of pigments was shown to reflect differences in the relative proportions of Chlorophyta, Cyanophyta and Bacillariophyta in these sites. Multivariate and univariate models strongly indicated that almost all soil variables (EC, W, TOC and TN) were important environmental correlates of pigment distribution. However, a significant amount of variation is independent of these soil variables and may be ascribed to local variability such as changes in microclimate at varying spatial and temporal scales. There are at least five possible sources of local variation: pigment preservation, temporal variations in water availability, temporal and spatial interactions among environmental and biological components, the local-scale patchiness of organism distribution, and biotic interactions.     

Effects of vanadium on freshwater phytoplankton photosynthesis

In six of the seven lakes studied, addition of vanadium at concentrations in the 2 to 165×10^?7 M range decreased photosynthetic rates of phytoplankton in six lakes. The depression was not a result of photosynthate loss. The response of phytoplankton photosynthesis to vanadium addition was assessed as the slope of photosynthetic rate (as percent of control) plotted against added vanadium concentration. We then used univariate and multivariate statistics to determine whether the response to vanadium (“slope”) was influenced by phosphorus availability (estimated by ³²P-turnover-time), phytoplankton biomass, and proportions of six taxonomic groups (as % of total phytoplankton biomass): Chlorophyta, Bacillariophyta, Chrysophyta, Pyrrophyta, Cryptophyta, and Cyanobacteria. Simple correlation analysis revealed that only biomass and cyanobacteria were significantly correlated (p<0.05) with the response to vanadium. To reduce redundancy among the eight ecological variables, we conducted a principal component analysis using data from the 22 experiments. The first two principal components accounted for 59% of the variance in the original variables. PC1 loaded highly and positively on biomass and cyanobacteria, and negatively on Bacillariophyta and Chrysophyta. PC2 loaded positively on Cryptophyta and Pyrrophyta. Only PC1 was significantly correlated (p <0.05) with the response to vanadium (“slope”). We conclude that lakes characterised by high phytoplankton biomass, high proportion of cyanobacteria, and low proportion of Bacillariophyta and Chrysophyta, are most vulnerable to inhibition of photosynthesis by vanadium. In the surface waters studied, dissolved vanadium at concentrations above the detection limit of 5.0×10^?8 M was found only in the inshore areas of Lake Erie and in Hamilton Harbour, Lake Ontario.     

Comparative Studies on the Green Algae Chlorella homosphaera and Chlorella vulgaris with Respect to Oil Pollution in the River Nile

The effect of oil pollution on growth and metabolic activitiesof the fresh water algae Chlorella homosphaera and C.vulgaris was studied. The study was conducted on two locationsin the river Nile, one is oil polluted and the other is notpolluted. The assemblage of the different algal groups wasmonitored in both locations. Chlorophyta was more dominant thanCyanophyta and Bacillariophyta in both locations during allseasons except in winter when Bacillariophyta is the mostdominant group. The presence of crude oil or its refineryproducts (solar and lubricating) in the culture media of algaemarkedly influenced their growth, proteins and nucleic acidcontents. The toxicity of oil was a concentration dependent. Thelow concentrations stimulated growth, protein content andnucleic acids, whereas high concentrations had an inhibitoryeffect. Although DNA and RNA responded similarly to crude oil inthe two tested organisms, DNA showed more sensitivity than RNAto solar oil. Lubricating oil had a little phytotoxic effect onnucleic acids. Different species of algae response differentiallyto oil pollution; Chlorella vulgaris can be referred to asoil-sensitive, while Chlorella homosphaera can toleraterelatively higher concentrations of oil.